sinProject-Inc/talk

/* eslint-disable @typescript-eslint/naming-convention */
/* eslint-disable @typescript-eslint/explicit-function-return-type */
/// <reference types="@sveltejs/kit" />
import { build, files, version } from '$service-worker'

// Create a unique cache name for this deployment
const CACHE = `cache-${version}`

const ASSETS = [
    ...build, // the app itself
    ...files, // everything in `static`
]

self.addEventListener('install', (event) => {
    // Create a new cache and add all files to it
    async function addFilesToCache() {
        const cache = await caches.open(CACHE)

        await cache.addAll(ASSETS)
    }

    event.waitUntil(addFilesToCache())
})

self.addEventListener('activate', (event) => {
    // Remove previous cached data from disk
    async function deleteOldCaches() {
        for (const key of await caches.keys()) {
            if (key !== CACHE) await caches.delete(key)
        }
    }

    event.waitUntil(deleteOldCaches())
})

self.addEventListener('fetch', (event) => {
    // ignore POST requests etc
    if (event.request.method !== 'GET') return

    async function respond() {
        const url = new URL(event.request.url)
        const cache = await caches.open(CACHE)

        // `build`/`files` can always be served from the cache
        if (ASSETS.includes(url.pathname)) {
            return cache.match(event.request)
        }

        // for everything else, try the network first, but
        // fall back to the cache if we're offline
        try {
            const response = await fetch(event.request)

            if (response.status === 200) {
                cache.put(event.request, response.clone())
            }

            return response
        } catch {
            return cache.match(event.request)
        }
    }

    event.respondWith(respond())
})